I was trying to create a sample android application without using android-studio.While I tried to sign the package by $APKSIGNER sign --ks mykey.keystore bin/hello.unaligned.apk I got the following error.
Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.UnsupportedClassVersionError: com/android/apksigner/ApkSignerTool has
been compiled by a more recent version of the Java Runtime (class file version 53.0), this version of the
Java Runtime only recognizes class file versions up to 52.0.
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:756)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:495)
I am using openjdk 1.8.0_265 on fedora32. Does it have something to do with jdk ?
version 53.0 means using java version 9, and you current jre is version 8, which can not run java 9 codes.
so download and configure to use jre 9.